Development and evaluation of chitosan–silk fibroin hydrogels for controlled drug delivery in wound healing applications

The future of biopolymer-based hydrogel formation holds a promising future for wound healing applications in terms of a controlled drug delivery system. This paper combined chitosan (CS) and silk fibroin (SF) in order to produce a hydrogel with an improved antibacterial effect, mechanical stability, and biocompatibility. A natural cross-linker, genipin, was used, providing tunable mechanical strength with cytocompatibility. Tensile testing, swelling, structural, and thermal tests of the hydrogels were conducted using the Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and X-ray diffraction (XRD). Structural and thermal properties of the CS-SF hydrogels were investigated. Model antibiotic and anti-inflammatory agents were encapsulated, and in vitro release was measured, demonstrating a controlled, sustained release profile. Superior cytocompatibility was confirmed through cell viability tests with fibroblasts and keratinocytes, indicating that the hydrogels can be applied to wounds. Further diffusion of the drug was also modelled using COMSOL Multiphysics, and the simulation outcomes were compared with experimental release data and found to be highly correlated. The findings demonstrate that under cross-linked genipin CS-SF hydrogels can successfully serve as wound dressings that could potentially enable tissue regeneration, and controlled delivery of therapeutic agents, with immense clinical translation potential in advanced wound care.